FIP Virtual Seminar: Whispering-gallery-mode microresonators: fundamentals and applications

Light-matter interactions are the fundamental basis for many phenomena and processes in optical devices. Whispering-Gallery-Mode (WGM) optical resonators trap light in a manner similar to a phenomenon found in the gallery spaces of St. Paul's Cathedral dome in London, where a single whisper (i.e., a sound wave) can be heard along the circular boundary of the architecture. Ultra-high-quality WGM optical micro-resonators provide unprecedented capability to trap light in a highly confined volume smaller than a strand of human hair; light beams can travel around the boundary of a WGM resonator over 106 times, significantly enhancing light-matter interactions, creating the potential for a wealth of new scientific discoveries and technological breakthroughs difficult to achieve by other devices. They have shown a great promise for a variety of fields of science, spanning from optomechanics to communication, non-Hermitian physics, sensing and metrology. In this talk, I will report the recent research discoveries from my group in this exciting field. I will present a few cases demonstrating the great potentials of high-Q WGM microresonators and microlasers for both fundamental science and engineering applications.